Method of forming a bead on a container body

ABSTRACT

In forming an external, annular raised projection or bead at the end of a container body, a tool having a cutout is brought into contact with a partially down-turned flange on the container body to effect doubling back of the flange toward the container body to dispose an outer marginal edge portion of the flange against the outside surface of the container body and, simultaneously, confine and mold an inner portion of the flange, which is contiguous with the end of the container body, into the cutout of the tool to thereby form the raised projection or bead at the end of the container body.

waited States Rateat 1 Saunders .Eune 12, 1973 [75] Inventor: William Thomas Saunders, Weirton,

W. Va.

[7 3] Assignee: American Can Company,

Greenwich, Conn.

22 Filed: June 30,1971

211 Appl. No.: 158,189

FOREIGN PATENTS OR APPLICATIONS 827,115 2/1960 Great Britain 113/120 AA Primary Examiner-Richard J I-Ierbst Attorney-Robert P. Auber, George P. Ziehmer, Leonard R. Kohan et a1.

[57] ABSTRACT In forming an external, annular raised projection or bead at the end ofa container body, a tool having a cutout is brought'into contact with a partially down-turned flange on the container body to effect doubling back of the flange toward the container body to dispose an outer marginal edge portion of the flange against the outside surface of the container body and, simultaneously, confine and mold an inner portion of the flange, which is contiguous with the end of the container body, into the cutout of the tool to thereby form the raised projection or bead at the end of the container body.

5 Claims, 5 Drawing Figures METHOD OF FORMING A BEAD ON A CONTAINER BODY BACKGROUND OF THE INVENTION The present invention broadly relates to the provision of a seamable container body and is more particularly concerned with a method of forming an external raised projection or bead at the end of a container body, where the bead will subsequently form part of a seam between the container body and an end closure.

Without being limited thereto, the present invention is particularly adapted for use in connection with a sheet metal container body of the easy-opening type where a plastic seam release strip is seamed between an end closure and the container body to serve as an integral holding member, the plastic seam release strip being positioned within the seam to abut the projection or bead formed on the container body in order to preclude inadvertent displacement of the seam release strip in relation to the end of the container body which would detrimentally affect the seam integrity, particularly, for products contained under pressure. Further, the plastic seam release strip is of the type which is manually removable from the seam formed by the end closure and the end of the container body without destruction or mutilation of either the container body of the end closure.

Heretofore, a seam release strip of this type has been used in connection with the seaming of a metal end closure to a container body made of compressible or nonrigid materials, for example, fiber or plastic materials, wherein, after assembly of the seam, a portion of the plastic strip is indented into the compressible material of the container body by a flange portion of the metal end closure, thereby causing a compression thinning of a portion of the container body and of a portion of the plastic strip in the area of the seam. As a result, the metal end closure is securely locked in place on the end of the container body in what may be designated as an indented or crimped seam. A plastic seam release strip incorporated in a seam of this type on a container body made of compressible material is disclosed in U. S. Pat. Nos. 3,330,436, 3,336,269 and 3,409,200.

The external raised projection or bead formed at the end of a container body by the novel method comprising the present invention is particularly useful for adapting a container body made of rigid material, for example, sheet metal which cannot be readily compressed or indented, for use with a plastic seam release strip. Accordingly by the present invention, there is provided a raised projection or bead formed at the end of the container body which prevents the plastic seam release strip from sliding toward the open end of the container body to thereby insure the integrity of the seam, particularly under pressurized conditions within the container body. More particularly, the present invention relates-to a novel method for forming a raised projection or bead at the end of a container body for incorporation in the seam and to serve, among other things, as a stop for a plastic seam release strip.

SUMMARY OF THE INVENTION In order to form an external, annular bead at the end of a container body, a longitudinally-extending end section of the container body is partially turned down so that its marginal edge resides in a position spaced radially from the container body side wall and longitudinally from the container body end. Then, the end section is moved radially inwardly toward, and in a longitudinal direction relative to, the container body side wall to dispose an outer marginal edge portion of the end section against the outside surface of the container body side wall and, simultaneously, confine and mold an inner portion of the end section, which is contiguous with the end of the container body, into the form of an annular raised projection or bead which extends radially outwardly from the outside surface of the container body side wall at the container body end.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a container body having an external, annular bead formed at the end of the container body by the novel method of the present invention;

FIG. 2 is an elevational view of the container body illustrating the container body partially in section and schematic relationship to forming tool means which are operated to perform the novel method steps of the present invention to form the external, annular bead at theend of the container body;

FIG. 3 is a schematic view illustrating the relationship of an enlarged, fragmentary vertical section of the container body end to the forming tool means upon completion of one forming step of the novel method, wherein a longitudinally-extending end section of the container body has been partially turned down to form a flange, the outer marginal edge portion of which resides in a position spaced radially and externally from the container body side wall and longitudinally from the container body end;

FIG. 4 is a schematic view illustrating the relationship of the enlarged, fragmentary vertical section of the container body end to the forming tool means upon completion of another forming step of the novel method, wherein the longitudinally-extending end section of the container body has been fully turned down in relation to the side wall of the container body and will no longer be moved in a longitudinal direction in relation to the container body end; and

FIG. 5 is a schematic view illustrating the relationship of the enlarged, fragmentary vertical section of the container body end to the forming tool means upon completion of still another forming step of the novel method, wherein an outer marginal edge portion of the longitudi'nally-extending end section of the container body has been disposed against the outside surface of the container body and an inner portion of the end section has been confined and molded into the form of an external, annular bead at the end of the container body.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT As a preferred and exemplary embodiment of the present invention, FIG. I shows a container body 10 having a tubular side wall 12 which is formed of sheet metal, such as tin plate or aluminum. The side wall 12 of the body 10 may have a side seam 14 of conventional construction or it may be a seamless body. While the body 10 is shown as being cylindrical, it may take on any of various cross-sectional configurations. In the case where the body 10 has a side seam 14, the lower end of the body 10 may be closed by an imperforate metal bottom end closure 16 which is secured thereto in a conventional double seam 18. In another case (not shown) where the side wall of the container body-is seamless, the lower end of the body will be closed by a bottom end wall which is integrally formed with the side wall. In either of the above cases, the upper end of the container body it) has an external, annular raised projection or bead 20 formed thereat, this bead 20 being adapted to be incorporated, along with a plastic seam release strip (not shown), into a seam (not shown) which secures an end closure (not shown) to the container body 10.

As shown in FIG. 2, the container body is initially provided with an outwardly and radially flared or curled marginal edge 22 which has been turned through an arc of ninety degrees or less. The flared edge 22 may be formed in any conventional manner on the container body 18 before the body 10 is positioned in alignment with the operative means of a bead forming station, generally designated 24, shown in FIG. 2.

At the bead forming station 24, a lifter pad element 26 engages the bottom end closure 16 of the container body lit) and thereby supports the container body 10. Alternatively, the lifter pad element 26 may engage the bottom edge (not shown) of the body side wall 12, instead of the bottom end closure 16, in the case where the end closure 16 has not yet been seamed onto the bottom edge of the side wall 12 of the container body 10. Also, at the station 24, a chuck element 28 has a lower cylindrical portion 30 of a diameter slightly less than the inside diameter of the container body 10 which fits into, engages and supports the upper section of the container body side wall 12 at the inside surface thereof, and an upper cylindrical portion 32 ofa diameter larger than that of the container body 10 which engages the flared marginal edge 22 of the container body side wall 12.

The lifter pad and chuck elements 26, 28 are fixedly mounted on shafts 34, 36 respectively which are aligned with the longitudinal axis of the container body and rotated by suitable drive means (not shown) at the same speed so that there is no relative rotary motion between the container body 10 and the lifter pad and chuck elements 26, 28. Further, the chuck element 28, concurrently as it is rotated, is movable longitudinally in relation to the container body 10 toward the lifter pad element 26 by any suitable means (not shown) from its initial position (represented by dash line P,) as shown in H6. 2 to a subsequently-assumed lower position (represented by dash line P in FIGS. 2 and 3) nearer to the lifter pad element 26 as shown in FIG. 3.

Further, at the station 24, a bead forming roll 38 is disposed radially outwardly from the container body 10 with the top surface 40 of the roll 38 contiguously facing, and parallel to, the annular bottom surface 42 of the upper cylindrical portion 32 of the chuck element 28 when the chuck element 28 has subsequently assumed its lower position (represented by dash line P,) as shown in FIG. 3. The roll 38 is fixedly mounted on a shaft 44 which is aligned parallel to the common axes of the shafts 34, 36 and the container body 10 and rotated by any suitable drive means (not shown). Concurrently as it is rotated, the roll 38 is movable radially inwardly toward, and perpendicular to, the common axes of the shafts 34, 36 and the container body 10, by any suitable means (not shown), from an initial position remote from the body side wall 12 as shown in FIGS. ,2 and 3 to a subsequently-assumed position contiguous with the body side wall 12 as shown in FIG. 5.

The roll 38 has a cutout or annular notch, generally designated 46, of a generally right-angled profile, defined at its upper longitudinal edge. As shown in FIG. 5, the cutout 46 together with an innermost marginal portion 48 of the annular bottom surface 42 of the upper cylindrical portion 32 of the chuck element 28 form a confining cavity, generally designated 50, in which the annular bead 20 is molded when the roll 38 has assumed its position contiguous with the top of the body side wall 12.

FIGS. 2 through 5 illustrate the various positions of the chuck element 28 and the forming roll 38 in relation to the top end section of the container body 10 during the performance of the novel method steps of the present invention at the bead forming station 24.

FIG. 2 shows the container body 10, which is initially provided with the flared marginal top edge 22, securely supported by, and rotating with, the lifter. pad and chuck elements 26, 28. As the chuck element 28 is moved longitudinally toward the lifter pad element 26 (from its initial position as represented by dash line P to its subsequent position as represented by dash line P the annular bottom surface 42 of the chuck element 28 is forced against the flared marginal edge 22 of the body side wall 12 which causes progressive bending and extending of a longitudinal end section 52 of the side wall 12 radially outwardly into the form of a partially down-turned flange 54 as shown in FIG. 3. The reason that the end section 52 bends and partially turns downwardly in this manner to form the flange 54 is that when the chuck element 28 is moved longitudinally downwardly to bend the flared marginal edge 22, the tendency is for the sheet metal or" end section 52 to maintain its initial arc of bend, with the result that the terminal raw metal edge 56 on the end section 52 starts to turn down eventually as progressively more of the sheet metal of end section 52 is bent outwardly by the longitudinally-moving chuck element 28.

Thus, FIG. 3 shows the position of the chuck element 28 in relation to the container body 10 at the completion of the first step of the novel method, wherein the partially down-turned flange 54 is formed with its terminating raw metal edge 56 residing in a position spaced radially and externally from the container body 10 and longitudinally from the end 58 of the container body 10. Also, FIG. 3 shows the position of the rotating forming roll 38 in relation to the rotating chuck element 28 and the container body 10 before commencement of another step of the novel method.

In the next steps, the rotating bead forming roll 38 is moved toward the container body 10 from a position remote from the body 10 as shown in FIG. 3 to a position contiguous with the body 10 as shown in FIG. 5, a transitory intermediate step of the bead forming operation performed at station 24 being shown in FIG. 4. As will be observed in FIG. 3, the raw metal edge 56 on the partially down-tumed flange 54 is disposed below an annular shelf 60 .which partially defines the cutout 46 of the forming roll 38. Therefore, as the roll 38 and its associated shaft 44 are translated or moved toward the container body 10, the outer cylindrical surface 62 of the .roll 38 engages the raw edge 56 and thereby forcibly moves an outer marginal edge portion 64 of the flange 54 toward, and, simultaneously, in a longitudinal direction in relation to, the container body 10 until the bead forming roll 38 reaches the position shown in FIG. 4.

Thus, FIG. 4 shows the position of the rotating forming roll 38 in relation to the rotating chuck element 28 and the container body at the completion of another step of the novel method, wherein the flange 54 has been fully turned down in relation to the side wall 12 of the container body 10 and will no longer be moved in a longitudinal direction in relation to the container body end 58. Also, FIG. 4 shows the position of the rotating forming roll 38 in relation to the rotating chuck element 28 and the container body 10 before commencement of the final step of the novel method.

In the final step, the rotating bead forming roll 38 continues its movement toward the container body 10 from its intermediate position as shown in FIG. 4 to its final position contiguous with the body 10 as shown in FIG. 5. As described hereinbefore, the cutout 46 and the innermost marginal portion 48 of the annular bottom surface 42 of chuck element 28 begin to form or define a confining cavity as the forming roll 38 approaches its final position contiguous with the container body 10 as shown in FIG. 5. Therefore, as the forming roll 38 approaches its final position, the outer cylindrical surface 62 of the roll 38 forcibly moves (or rolls) the outer marginal edge portion 64 of the flange 54 toward the container body 10, causing, simultaneously therewith, an inner portion 66 of the flange 54 to become increasingly confined into the cavity 50 until eventually the inner portion 66 is completely molded in the cavity 50 into the form of the external, annular bead simultaneously as the inner surface 68 of the outer marginal edge portion 64 longitudinally abuts a portion of the outside surface of the body side wall 12.

Although the performance of the steps of the novel method by the operative means at the bead forming station 24 has been above-described in one particular way, alternative modes of operation of the operative means would be apparent. For example, instead of the chuck element 28 being lowered toward the lifting pad element 26, the lifting pad element 26 may be raised toward the chuck element 28, or even both elements 26, 28 moved toward each other. Further, instead of moving the forming roll 38 radially inwardly toward the container body 10, the container body 10 may be moved toward the forming roll 38, or even both moved toward each other. Still further, in forming the bead 20, either one or both of the lifting pad and chuck elements 26, 28 may be positively driven and the forming roll 38 freely rotatable, or the forming roll 38 may be positively driven and one, both or neither of the lifting pad and chuck elements 26, 28 positively driven.

The steps of the novel method for forming a bead of the type shown in FIGS. 1 and 5 may be utilized on either a seamless container body or on a container body of the type having a conventional longitudinal side seam, the bead 20 being formable across the conventional lapped and adhesively bonded, soldered or welded side seam. It will be observed that by the construction of the exterior, annular head 20 by the novel method, the raw metal edge 56 will be carried externally of the container body 10 out of contact with the contents of the container. Further, this construction of the bead 20 eliminates exposure of sharp edges and thereby protects the consumer, particularly enhancing reclosure conditions.

Although the bead 20 is illustrated in the drawings as having a somewhat rectangular cross-sectional configuration, it will be apparent that the steps of the novel method may be applied to formation of various and different cross-sectional configurations of the bead 20 ineluding arcuate and straight-line portions or combinations thereof.

Also, it is to be understood that the expressions up per, lower, top" and bottom used hereinbefore are for the purpose of convenience in describing the relative orientation of the parts and are not to be considered as limitations on the structure disclosed.

It is thought that the invention and many of its attendant advantages will be understood from the foregoing description and it will be apparent that various changes may be made in the steps of the method described and their order of accomplishment without departing from the spirit and scope of the invention or sacrificing all of its material advantages, the method hereinbefore de' scribed being merely a preferred embodiment thereof.

I claim:

1. The method of forming an external annular bead at the end of a container body made of a substantially non-compressible material, comprising the steps of:

bending a longitudinal end section of the container body radially outwardly and longitudinally in relation to said container body; and

displacing said end section radially inwardly toward,

and longitudinally in relation to, said container body to fully turn down said end section, to cause a longitudinal abutting of substantially the length of the inner surface of an outer marginal edge portion of said end section against said container body so that the terminal edge of said end section faces the end of said container body opposite to that of said annular bead, and simultaneously, to cause molding of an inner portion of said end section which is contiguous with the end of said container body, into the form of an external annular bead at the end of the container body, and to cause said terminal edge to be positioned externally of said annular bead.

2. The method of forming an external annular bead at the end of a container body made of substantially non-compressible material, comprising the steps of:

bending a longitudinal end section of the container body radially outwardly and longitudinally in relation to said container body;

engaging said end section at the terminal edge thereof; and

displacing said end section radially inwardly toward,

and longitudinally in relation to, said container body to cause abutting of substantially the length of the inner surface of an outer marginal edge portion of said end section against said container body so that the terminal edge of said end section faces the end of said container body opposite to that of said annular bead, and, simultaneously, to cause molding of an inner portion of said end section, which is contiguous with the end of said container body, into the form of an external annular bead at the end of the container body, and to cause said terminal edge to be positioned externally of said annular bead.

3. The method of forming an external annular bead at the end of a container body made of a substantially non-compressible material, comprising the steps of:

forming a longitudinally-extending end section of the container body into a partially down-turned flange on the end of the container body by bending said end section radially out-wardly through a path of revolution defined by an arc of 90 or less;

displacing said partially down-turned flange radially inwardly toward said container body and longitudinally in relation to the end of said container body to fully turn down said flange in relation to said container body; and

displacing said fully down-turned flange radially inwardly toward said container body to cause abutting of the inner surface of an outer marginal edge portion of said flange against said container body so that the terminal edge of said flange faces the end of said container body opposite to that of said annular bead, and, simultaneously, to cause molding of an inner portion of said flange, which is contiguous with the end of said container body, into the form of an external annular bead at the end of the container body, and to cause said terminal edge to be positioned externally of said annular bead.

4. The method of forming an external annular bead at the end of a container body made of a substantially non-compressible material, comprising the steps of:

forming a longitudinally-extending end section of the container body into a partially down-turned flange on the end of the container body by bending said end section radially outwardly through a path of revolution defined by an arc of 90 or less;

engaging said partially down-turned flange at the terminal edge thereof;

displacing said partially down-turned flange radially inwardly toward said container body and longitudinally in relation to the end of said container body to fully turn down said flange in relation to said container body; and

displacing said fully down-turned flange radially inwardly toward said container body to cause abutting of the inner surface of an outer marginal edge portion of said flange against said container body so that the terminal edge of said flange faces the end of said container body opposite to that of said annular bead, and, simultaneously, to cause molding of an inner portion of said flange, which is contiguous with the end of said container body, into the form of an external annular bead at the end of the container body, and to cause said terminal edge to be positioned externally of said annular bead.

5. The method of forming an external annular bead at the end of a container body made of a substantially non-compressible material, comprising the steps of:

progressively bending a longitudinally-extending end section of the container body radially outwardly and longitudinally in relation to said container body through a path of revolution defined by an arc of or less;

engaging said end section at the terminal edge thereof;

displacing said end section radially inwardly toward said container body and longitudinally in relation to the end of said container body;

abutting the inner surface of an outer marginal edge portion of said end section against said container body so that the terminal edge of said section faces the end of said container body opposite to that of said annular bead; and

simultaneously with said abutting step, molding an inner portion of said end section, which is contiguous with the end of said container body, into the form of an external annular bead at the end of the container body, and to cause the terminal edge to be positioned externally of said annular bead. 1K 

1. The method of forming an external annular bead at the end of a container body made of a substantially non-compressible material, comprising the steps of: bending a longitudinal end section of the container body radially outwardly and longitudinally in relation to said container body; and displacing said end section radially inwardly toward, and longitudinally in relation to, said container body to fully turn down said end section, to cause a longitudinal abutting of substantially the length of the inner surface of an outer marginal edge portion of said end section against said container body so that the termInal edge of said end section faces the end of said container body opposite to that of said annular bead, and simultaneously, to cause molding of an inner portion of said end section which is contiguous with the end of said container body, into the form of an external annular bead at the end of the container body, and to cause said terminal edge to be positioned externally of said annular bead.
 2. The method of forming an external annular bead at the end of a container body made of substantially non-compressible material, comprising the steps of: bending a longitudinal end section of the container body radially outwardly and longitudinally in relation to said container body; engaging said end section at the terminal edge thereof; and displacing said end section radially inwardly toward, and longitudinally in relation to, said container body to cause abutting of substantially the length of the inner surface of an outer marginal edge portion of said end section against said container body so that the terminal edge of said end section faces the end of said container body opposite to that of said annular bead, and, simultaneously, to cause molding of an inner portion of said end section, which is contiguous with the end of said container body, into the form of an external annular bead at the end of the container body, and to cause said terminal edge to be positioned externally of said annular bead.
 3. The method of forming an external annular bead at the end of a container body made of a substantially non-compressible material, comprising the steps of: forming a longitudinally-extending end section of the container body into a partially down-turned flange on the end of the container body by bending said end section radially out-wardly through a path of revolution defined by an arc of 90* or less; displacing said partially down-turned flange radially inwardly toward said container body and longitudinally in relation to the end of said container body to fully turn down said flange in relation to said container body; and displacing said fully down-turned flange radially inwardly toward said container body to cause abutting of the inner surface of an outer marginal edge portion of said flange against said container body so that the terminal edge of said flange faces the end of said container body opposite to that of said annular bead, and, simultaneously, to cause molding of an inner portion of said flange, which is contiguous with the end of said container body, into the form of an external annular bead at the end of the container body, and to cause said terminal edge to be positioned externally of said annular bead.
 4. The method of forming an external annular bead at the end of a container body made of a substantially non-compressible material, comprising the steps of: forming a longitudinally-extending end section of the container body into a partially down-turned flange on the end of the container body by bending said end section radially outwardly through a path of revolution defined by an arc of 90* or less; engaging said partially down-turned flange at the terminal edge thereof; displacing said partially down-turned flange radially inwardly toward said container body and longitudinally in relation to the end of said container body to fully turn down said flange in relation to said container body; and displacing said fully down-turned flange radially inwardly toward said container body to cause abutting of the inner surface of an outer marginal edge portion of said flange against said container body so that the terminal edge of said flange faces the end of said container body opposite to that of said annular bead, and, simultaneously, to cause molding of an inner portion of said flange, which is contiguous with the end of said container body, into the form of an external annular bead at the end of the container body, and to cause said terminal edge to be positioned externally of said annulAr bead.
 5. The method of forming an external annular bead at the end of a container body made of a substantially non-compressible material, comprising the steps of: progressively bending a longitudinally-extending end section of the container body radially outwardly and longitudinally in relation to said container body through a path of revolution defined by an arc of 90* or less; engaging said end section at the terminal edge thereof; displacing said end section radially inwardly toward said container body and longitudinally in relation to the end of said container body; abutting the inner surface of an outer marginal edge portion of said end section against said container body so that the terminal edge of said section faces the end of said container body opposite to that of said annular bead; and simultaneously with said abutting step, molding an inner portion of said end section, which is contiguous with the end of said container body, into the form of an external annular bead at the end of the container body, and to cause the terminal edge to be positioned externally of said annular bead. 